The government said about 800 young Aussies could benefit from the extra funding, the ABC reports.

Ley told reporters that the government's new cancer trial scheme was crucial for young people to take part in possible breakthrough treatments.

"This funding is critically important to leverage the big pharmaceutical companies into providing new cutting-edge therapies for young people with cancer," she said.

"This not only has the benefit of improving outcomes, but helps with side-effects in the long-term. In short, this is a fantastic initiative that will improve the outcome and survival of young people with cancer."

She said the coalition would continue to make tough decisions when it came to listing of medicines on the PBS.

The government scheme will also change age restriction rules to allow more teenagers and young adults to participate in trials.

In Sydney, Shorten vowed to scrap moves by the government that he said would see the cost of a visit to the GP increase.

Shorten's promise would reportedly cost the federal budget $971 million over the next 4 years. Labor says that amount will be made up by not cutting company tax rates like the coalition plans to do.